package com.atguigu.day12.morning.m1;

class A{
    public String show(D obj){
        return ("A and D");
    }
    public String show(A obj){
        return "A and A";
    }
}
class B extends A{
    public String show(B obj){
        return "B and B";
    }
    public String show(A obj){
        return "B and A";
    }
}
class C extends B{

}
class D extends B{

}